Habitat
Buff-breasted Sandpipers nest only in the High Arctic of northernmost Alaska and Canada. Males display in prominent raised areas in this environment, usually along ridges, bluffs, and banks near creeks and rivers. Here, water sedge, dwarf willow, horsetail, mountain-avens, and cottongrass are common plants. Similarly, females build the nest on dry slopes or other raised locations, often not far from a stream. Other occupants of upland tundra habitat include Baird’s Sandpipers and American Golden-Plovers, and these three species are often found together during migration as well. They seek out mostly dry, flat habitats including sod farms, prairies, and many kinds of agricultural fields, so long as they are not covered by water or heavy vegetation. Newly planted fields, recently harvested fields (including potato, soy, and rice fields), pastures, and many places that maintain short, grassy lawns such as cemeteries, industrial parks, and airports attract them. Migrants in South America even turn up on sandy river islands in the Amazon basin. During winter in South America, most Buff-breasted Sandpipers use grassland habitats, including grazed pastures, farm fields, and native pampas. Sites with glassworts, saltgrass, cordgrass, and Augustine grass attract them, but they also visit shallow wetland sites and rice fields, particularly in the afternoon, when they drink and bathe.
Back to topFood
Buff-breasted Sandpipers eat mostly insects, spiders, isopods (pillbugs), snails, and earthworms. They forage for insects much like plovers, walking along quickly, then suddenly stopping to look and listen, then seizing prey with the short, fine bill. Unlike most other sandpipers, they do not probe into the earth for hidden prey, though they can extract worms and grubs that are partly exposed. Their insect diet includes adults and larvae of beetles, ants, midges, flies, craneflies, moths, butterflies, crickets, and grasshoppers. They also consume small quantities of seeds, of plants such as knotweeds, pondweeds, and spikerushes.
Back to topNesting
Nest Placement
Females select nest sites on the ground in dry, well-drained sites in tundra, often near a creek or river.
Nest Description
Females make a scrape on the ground, usually a place hidden by sedges, and line it with lichens, leaves, moss, sedges, and other plant material found near the scrape. Nests average about 3.6 inches across and 1.8 inches deep.
Nesting Facts
Clutch Size: | 2-5 eggs |
Egg Description: | Dull white, buff, or olive-buff heavily blotched with darker brown. |
Condition at Hatching: | Active and covered with down. |
Behavior
As soon as they arrive on tundra nesting grounds, male Buff-breasted Sandpipers begin their rousing courtship displays. Several males (rarely up to 20) form a loose group (all within sight of each other) known as an "exploded lek," often on dry patches of tundra near river bends. These leks last for several days. Some males frequent the same lek location, whereas others move from lek to lek, taking short flights or in some cases wandering for hundreds of miles. Their displays are unusual among shorebirds, involving at least 17 different postures and behaviors. Most often, males crouch and raise the tail and one wing, waving the wing slowly to show the bright white undersurface. They also leap into the air and flutter the wings in a balletic display. When a male has attracted the attention of a female, he raises and opens both wings, raises the bill and head, puffs out the breast, stands on tip-toe, and moves forward like a wind-up toy, making the wings move up and down. A receptive female opens and raises the wings, then turns her back toward the male. Leks can seem chaotic in their activities, as males often seek to disrupt other males’ displays when females are present. Some males even try to distract others by mimicking female behavior, and it is common to see males attempt to mate with other males at leks. Male and female do not form a pair bond; the females select nest sites, build nests, and raise young without help from males. After the breeding season, Buff-breasted Sandpipers gather in flocks for migration, like most shorebirds. They arrive on wintering grounds in flocks but soon begin to establish feeding territories there. Males often display on wintering grounds and sometimes during migration.
Back to topConservation
Buff-breasted Sandpiper populations once numbered in the hundreds of thousands to millions, but by the 1920s hunting, overgrazing, conversion of prairie to cropland, and other landscape changes had brought this species close to extinction. Their numbers increased slightly after shorebird hunting was banned in the early 20th century, but are thought to be declining again. Partners in Flight estimates the global breeding population at 56,000, rates the species a 14 out of 20 on the Continental Concern Score, and includes the species on its Yellow Watch List for species with declining populations. Habitat loss and energy development projects (including oil/gas and wind power) threaten the sites these birds use for display, nesting, and migration. The effects of climate change in the Arctic, including both sea-level rise and habitat changes, are likely to render some current nesting areas unsuitable.
Back to topCredits
McCarty, John P., L. LaReesa Wolfenbarger, C. D. Laredo, Peter Pyle and R. B. Lanctot. (2017). Buff-breasted Sandpiper (Calidris subruficollis), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.
Partners in Flight (2017). Avian Conservation Assessment Database. 2017.
Sibley, D. A. (2014). The Sibley Guide to Birds, second edition. Alfred A. Knopf, New York, NY, USA.